Plastic tube for pastes and other viscous materials



july 6, 1954 sMlTH 2,682,974

PLASTIC TUBE FOR PASTES AND OTHER VISCOUS MATERIALS Filed July 9, 1948 INVENTOR'. Harry 17. 5104111 Patented July 6, 1954 PLASTIC TUBE FOR PASTES AND' OTHERr VISCOUS MATERIALS Harry-A., Smith, New- York, N. .Y...

Application July' -9,- 1948, Serial No. 371935 2 Claims.

My present; invention relates; to: plastic col; lapsible tubes, containerszandtha like, andaims. to: provide certain improvements; thereinr.

Collapsible tubes for packaging-anddispensin toothpaste, medicated: ointments, paints; and, other viscous materialsrare; currently madepf tin, lead; aluminumand; the like: Aside-from being costly to produce because-of the methods of;man-. ufacturing the tubes and ornamenting them prior to filling, the metals used for said purposearetnow being stock-piled for defense purposes; .and.-in-.the' event of a war theymay be; so restricted asgto. preclude their use formaking collapsiblegtubea. Moreover, many manufacturers of toothpasteand medicated ointmentshavelong sought for a collapsible tube made of 1plastic:which1.may be transparent or translucent, which will be-iime pervious to the essential oils and;flavorings. usedv in compoundinggsuch products,- and-,whichnwill. be flexible to the degrees-that the tube may be squeezed in the palm of ;the hand". to dispense the contents; without recourse to rolling up the tube as the contents thereof are discharged;

It is accordingly the objects of my-presentiinwvention to provide a collapsible tube from plastic material which will be relatively cheap; which; will be transparent or translucent'as desired; which will be impermeable to moisture, oils and; flavorings used in pharmaceutical-preparations, cosmetics and perfumes; which will be pleasingto the feel of the hands, and which will enable ad vertising or decorativematter tobe-applied to;the material fromwhich the tube'is made, prior to fabricating the tube. Myinvention also con-- templates a novel valvedisposed within-theheadi of the tube--whichvalve willnormally seat to prevent drying or evaporation of the; tube contents in the event that the cap :is inadvertently not replaced on thetube,

The foregoing and other objects of myinvene tion not specifically; enumerated I accomplish by: forming the. collapsible tube entirely of;v plastic. material and preferably of thermoplasticina terial. However, since many of said materials are permeable to certainoils and flavoringsor are attacked by others, and in view of my desire to form at least the outer surface material of the tube from stock which can be pre-ornamented and imprinted, the body of" the collapsible tube. is preferably formed-of a plurality of laminations. of the-same or dilferent thermoplastic material depending upon the'characteristics desired for. the finished tube, which laminations may be either of preformed tubular shape or of'sheet' material which may be wound or rolled into "tubular form and assembled so as to provide the" outermost lamination with the pre-imprinted matter. The: invention iIl'itS various aspects will' be better. understoodjrom. the detailed descripetionwhichfollows when considered in connecttion. with the. accompanying,- d-ra-wings showing; twoembodiments, and wherein:.

Figure 1. is: an elevationoffai collapsibletube Fig-,6 isa section'taken'substantially along the planeofthe linet-fi of Fig. 2.

Fig. 7 is a.section:correspondingto Fig. 6 and showinganother embodiment of the body con struction of the. tube.

Referringto the :drawings, the collapsible tube embodying. my inventionmay be said to consist of a head iii, a-closurecap II and a body portion. I 2, all .made: of plastic '1 material.

The-head lfi 'is perferably formed ofa suitablethermoplastic. material oftsufiicient thickness to be rigid and? dimensionally stable, and has an axial passage ofvarious diameters extending therethrough; the passage it of smallest diameter being intermediate thepassages Hi'and ii; the latter passage forming-withthe passage 13a: shoulderorrvalve'gseati ifiiupon which a flap valve ll is;mounted.. Thefiapwvalve I! is of smallerarea than the passage-I 5, but of sufficient size to'provide a closure forrthe passage 53'. As is conventional, the outer end of the head may be externally screwethreaded; as indicated at 15, to-accommodate;theclosure cap H. The head I!) maybe formed of any" suitable thermoplastic material which canbemolded or extruded, and I prefergto use polyethylene-for saidpurpose. The fiap valve llisalso-preferably formedof polyethylene which, insheetform, is resilient and has theinherent property of returning to its initial shapeafterbeing-deformedby a force less than its elasticplimit. As herein shown, the flap valve I l is in ,the form-of a rdisc :of polyethylene which isheat-bondedto the shoulder 16 along a limited area of engagement; indicated'at' 19, to provide a hinge-joint fonthe valve.

Theclosu-re. cap 5 trnay. beformed in any well known manner fromplastic material'and is internally-screw-threaded for engagement with the screw-threads on the ."head and is preferably externally knurled orfluted, asindicatedu at 25.

X The. body portion i2.of thetube is preferably formed of a plurality of laminationsv of. flexible thermoplastic material, two laminations 2|v and 22 being'shown in theembodiment disclosed, in Figs; 1 to5', and'three laminations 23, 2d, and 25 spirally wound'upon one another, being shown intheembodiment of-Fig. 7; The laminations 2| and 22 may-be of the-same or-different-thermoplasticv material. depending upon the-characteristics; desiredifor the; finished tube.

These -lam-i-- nations may be either of preformed tubular shape or of sheet material which may be wound or rolled into tubular form and seamed in situ. It is desirable that the outermost lamination be of a character of material which can be ornamented and imprinted prior to forming the tube so that the high cost of ornamenting and/or printing the tube during the manufacture thereof may be avoided. The number and character of the laminations forming the body of the tube will also depend upon the permeability of the laminating material to the substances to be packaged in such tubes and, of course, it is preferable that at least one of the laminations will be impermeable to moisture, essential oils and flavorings used in pharmaceutical preparations, cosmetics and perfumes, while one or more of the remaining laminations may be permeable to a limited extent to such substances. I have found that by making the inner lamination 2| of polyethylene and the outer lamination 22 from a polymer of vinylidene chloride such as Saran or Geon, the tube will have the necessary properties for packaging tooth pastes, pharmaceutical preparations and cosmetics. By forming the inner lamination 2| of polyethylene it may be given a thickness sufficient to afford ample body and strength to the tube, in which case the outer lamination which may be formed of "Saran or Geon may be relatively thin, e. g., about 0.002 of an inch thick. If desired, the tube portion may be formed from a continuous sheet of suitable thermoplastic material spirally wound upon itself to provide a plurality of laminations, as shown in Fig. 7, in which case the portion of the sheet which will form the outermost convolution will be pre-ornamented or imprinted so that the body portion of the tube, when formed, will be ornamented without further recourse to a separate ornamenting or imprinting operation.

Although the body portion l2 may be made in various ways I prefer to form the inner lamination 2| of tubular stock either separately from the head [9 or integrally therewith by an extruding operation. Where the lamination 21 is formed separately from the head it may be heat-sealed around the cylindrical portion a of the head in any preferred manner. The lamination 2| after being secured to the head, while preferably on a mandrel, may have the lamination 22 wound therearound and the overlapping longitudinal edges 26 and 21 thereof sealed in situ. Where said outer lamination is formed of Saran it is preferable to heat-seal the longitudinal overlapping edges by high frequency induction current which will cause shrinkage of the head-engaging end of the lamination around the head and over the shoulder 28 thereon, as indicated at 29, to provide a secure grip onto said head. In making the tube body portion from a lamination 2| of polyethylene and a lamination 22 of Saran, it is preferable to form the Saran lamination of a length to extend a substantial distance beyond the ends of the polyethylene lamination, as shown for example, prior to sealing at the bottom of Fig.

for the reason that Saran has a high shrinkage factor upon sealing.

When a tube such as shown in Fig. 2 has been formed, the head is capped by the closure cap I I and the tube is filled through its open bottom end in a conventional manner. The open end of the polyethylene inner lamination is then heatsealed by the hot plate method through the Saran lamination by a sealing temperature vto seal the same.

sufilcient to heat-seal the polyethylene but insufficient to heat-seal the Saran. The open end of the Saran tube may then be sealed by applying a proper heat-sealing means thereto or by subjecting said open end to high frequency induction current to accomplish said sealing. In this connection it may be stated that in view of the extremely low dielectric los of polyethylene, it is practically unaffected by the induction sealing of th Saran.

The filled tube is now ready for use and in dispensing contents from said tube the cap I l is withdrawn and pressure is applied to the walls of the tube either in the conventional manner or by grasping the same in the hand and squeezing it between the palm and fingers. Under the application of such pressure, the flap valve 1 I will open, as shown in Fig. 5, to permit the contents to fiow from the head. After the desired amount of substance has been dispensed, the release of pressure on the tube wall will, because of its inherent resiliency, tend to return to its original form and in the course of such action any of the substance contained in the passage 15 below the open flap valve I? will ooze back into the tube owing to the atmospheric pressure thereon and the inherent tendency of the valve I I to seat upon the shoulder Hi. The cap H may then be applied to the tube Should the user inadvertently forget to re-apply the cap, the closing of the valve I! will operate as a closure for the passage i3 and thus prevent, to a substantial degree, the drying of the tube contents.

While I have shown and described certain preferred embodiments of my invention it is to be understood that changes in constructional details, materials used and the methods employed in forming the tube may be varied within the range of engineering skill without departing from the spirit of the invention as defined in the appended claims.

What I claim is:

l. A collapsible tube having a body portion wholly formed of a plurality of laminations of flexible thermoplastic material, at least one of said laminations being relatively thick and formed of polyethylene and at least one of said laminations comprising a polymer of vinylidene chloride and being relatively thin compared to the polyethylene lamination.

2. A collapsible tube having a body portion formed of a relatively thick inner lamination of polyethylene and an outer lamination comprising a polymer of vinylidene chloride, said outer lamination being relatively thin compared to the inner laminations.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,322,426 Gearhart Nov..18, 1919 1,846,726 Isaacks Feb, 23, 1932 1,881,488 Gleason Oct. 11, 1932 2,105,615 Romeis Jan. 18, 1988 2,252,854 I-Iubner et a1. Aug. 19, 1941 2,268,462 Sacksenroder et a1. Dec. 30, 1941 2,269,661 Gurwick Jan. 13, 1942 2,274,258 Roselle Feb. 24, 1942 2,411,244 Bogoslowsky 1 Nov. 19, 1946 2,430,995 Roos Nov. 18, 1947 2,484,965 Slaughter Oct. 18, 1949 2,485,885 I-Ioope Oct. 25, 1949 2,539,154 Nissen Jan. 23, 1951 

1. A COLLAPSIBLE TUBE HAVING A BODY PORTION WHOLLY FORMED OF A PLURALITY OF LAMINATIONS OF FLEXIBLE THERMOPLASTIC MATERIAL, AT LEAST ONE OF SAID LAMINATIONS BEING RELATIVEL THICK AND FORMED OF POLYETHYLENE AND AT LEAST ONE OF SAID LAMINATIONS COMPRISING A POLYMER OF VINYLIDENE CHLORIDE AND BEING RELATIVELY THIN COMPARED TO THE POLYETHYLENE LAMINATION. 